Well Completion Arrangement and a Method for Preparing a Well for Abandonment

ABSTRACT

A well completion arrangement and method is for removing at least a portion of a line running in an annulus between a tubing and a casing in a well. The arrangement comprises
     at least two clamping means spaced apart in the longitudinal direction of the tubing and fixed thereto, the clamping means being configured for fixing the line with respect to tubing,   a splitting means for releasing the line from the interval defined by at least an upper clamping means and a lower clamping means of the at least two clamping means,   a line manipulator apparatus for activating said release of the line, and   a line retrieval apparatus for displacing into the tubing the portion of the line from said interval, thereby removing the line from the annulus.

This invention relates to controlled splitting, release and removal ofat least one line from a defined section of an annulus between a tubingand a casing of a well related to the production of hydrocarbons. Morespecifically the present invention relates to a well completionarrangement for removing at least a portion of a line running in anannulus between a tubing and a casing in a well and a method forpreparing a well for abandonment.

The main objective with the present invention is to provide anarrangement and a method for controlled removal of at least a section ofat least one line in a well.

In this document the term line is meant to be any line running in anannulus between a tubing and a casing. Such a line may be a controlline, a communication line, a chemical injection line and similar. Theline may be used to transmit electric or fiber-optic signals, electricpower, hydraulic fluid pressure, scale inhibiting chemicals and similar.For the sake of simplicity the line is commonly referred to as controlline, but can be any line mentioned above.

When abandoning a well in an oil/gas field and related wells, theshutting down of the well has to be conducted according to relevantregulatory practices. The general term for such operations is “plug andabandonment”. The regulatory practices define the number and nature ofbarriers that need to be permanently established between the hydrocarboncarrying formation and the surface. Moreover, the practices define whatequipment that can be left permanently in the well and what equipmentthat has to be removed.

Traditionally, plug and abandonment operations have been conducted usingrigs or tailor made jack systems, cutting the tubing and the controlline deep in the well, and pulling everything out to the surface.Subsequent to this, the well is cemented, and the top sections of thecasing and conductors are cut and removed.

For subsea wells, the use of rigs for plug and abandonment operationsbecomes extremely expensive. Jack systems for similar operations doesnot currently exist, but may be developed in the future. Anyhow, bothrig and jack operations would be very expensive to use for plugging andabandoning subsea wells.

The regulations related to plug and abandonment work do allow for thetubing to be left as part of the permanently cemented equipment left inthe well. However, control lines used to communicate and/or operatedownhole equipment such as sensors and flow control devices cannot beleft permanently in the well, as they represent a potential for futureleakage paths through the cement. The control lines are typicallyclamped to the outside of the production tubing, and in most cases thereis no practical way of removing the control lines without cutting andpulling the tubing itself.

The invention has as its object to remedy or at least reduce one or moredrawbacks of the prior art.

The object is achieved through features as specified in the descriptionbelow and in the subsequent Claims.

In this document splitting will mean any kind of dividing of the line,such as cutting, clipping, pulling apart, such as pulling apart over apre-created weakpoint or coupling in the line, squeezing apart anddisconnecting by means of operating line couplings designed for thispurpose.

In a first aspect of the present invention there is provided a wellcompletion arrangement for removing at least a portion of a line runningin an annulus between a tubing and a casing in a well, wherein thearrangement comprising:

-   -   at least two clamping means spaced apart in the longitudinal        direction of the tubing and fixed thereto, the clamping means        being configured for fixing the line with respect to tubing;    -   splitting means for releasing the line from the interval defined        by at least an upper clamping means and a lower clamping means        of the at least two clamping means;    -   a line manipulator apparatus for activating said release of the        line;    -   a line retrieval apparatus for displacing into the tubing the        portion of the line from said interval, thereby removing the        line from the annulus.

The clamping means may constitute a portion of the tubing connecting twotubing joints, or associated crossover piping towards the tubing.

The arrangement may be provided with an allocation means for controllingthe position of at least the manipulator apparatus with respect to theholding means.

The line manipulator apparatus may comprise the line retrievalapparatus.

The splitting means may be provided in at least one of the clampingmeans.

Alternatively, the splitting means may be provided in the manipulatorapparatus.

Thus, the splitting means may be adapted to cut through a portion of theclamping means.

The line manipulator may further be provided with gripping means adaptedfor engaging a profile of the clamping means. The profile may bearranged adjacent of the holding means.

The retrieval apparatus may be a flow and/or pressure inducing apparatusarranged for displacing the line from the outside to the inside of thetubing. In one embodiment of the present invention the flow and/orpressure inducing apparatus is a pump located on the surface of thewell.

In a second aspect of the present invention there is provided a methodof preparing a well for abandonment, the method comprising the steps of:

-   -   incorporating at least two spaced apart clamping means in a        tubing during completion of the well, the clamping means being        provided with a holding means for fixing a line with respect to        the clamping means, the line running in an annulus between the        tubing and a casing;    -   providing splitting means for releasing the line at least at an        upper clamping means and at a lower clamping means of the at        least two clamping means;    -   providing an apparatus for inducing said release of the line;        and    -   providing an apparatus for displacing into the tubing the        portion of the line from the interval defined by at least the        upper clamping means and at the lower clamping means of the at        least two clamping means.

The following describes a non-limiting example of a preferred embodimentillustrated in the accompanying drawings, in which:

FIG. 1 is a generic sectional view of a well for the production ofhydrocarbons;

FIG. 2 illustrates a prior art plug and abandonment technique;

FIG. 3 illustrates a desired scenario for plugging and abandonment,which is sought by means of the invention described herein;

FIG. 4 illustrates prior art attachment techniques for securing acontrol line to production tubing;

FIG. 5 illustrates a generic well completion according the presentinvention;

FIG. 6 illustrates the same well completion as shown in FIG. 5, butwhere the control line has been removed;

FIG. 7 illustrates the completion from FIGS. 5-6 after the well has beencemented;

FIG. 8 a illustrates in a sectional view one embodiment of a bottomclamp further to the invention herein;

FIG. 8 b illustrates a side view of FIG. 8 a seen from right to left;

FIG. 9 a illustrates the bottom clamp in FIG. 8 a where a wirelinemanipulation tool is used to create a cut and perform an initial releaseoperation of the control line;

FIG. 9 b illustrates a side view of FIG. 9 a seen from right to left;

FIG. 10 a illustrates in a sectional view an embodiment of anintermediate clamp further to the invention herein;

FIG. 10 b illustrates a side view of FIG. 10 a seen from right to left;

FIG. 11 a illustrates the intermediate clamp of FIG. 10 a, and awireline manipulation tool used to perform a release operation of thecontrol line;

FIG. 11 b illustrates a side view of FIG. 11 a seen from right to left;

FIG. 12 a illustrates a sectional view of one embodiment of a top clampfurther to the invention herein;

FIG. 12 b illustrates a side view of FIG. 12 a seen from right to left;

FIG. 13 a illustrates the top clamp of FIG. 12 a, and a wirelinemanipulation tool used to perform a cut and release operation of thecontrol line;

FIG. 13 b illustrates a side view of FIG. 13 a seen from right to left;

FIG. 14 a illustrates the top clamp of FIGS. 12 a-13 a, after thecontrol line has been cut and released, and shows the initial stage ofthe control line removal operation;

FIG. 14 b illustrates a side view of FIG. 14 a seen from right to left;

FIG. 15 a illustrates a sectional view of a top clamp in anotherembodiment, and a wireline manipulation tool used to perform a cut andrelease operation of the control line;

FIG. 15 b illustrates a side view of FIG. 15 a seen from right to left;

FIG. 16 a illustrates the top clamp of FIG. 15 a, after the control linehas been cut and released, and shows the initial stage of the controlline removal operation;

FIG. 16 b illustrates a side view of FIG. 16 a seen from right to left;

FIG. 17 a illustrates a sectional view of another embodiment of a topclamp further to the invention herein;

FIG. 17 b illustrates a side view of FIG. 17 a seen from right to left;

FIG. 18 a illustrates the top clamp of FIG. 17 a, and a wirelinemanipulation tool used to perform a cut and release operation of thecontrol line;

FIG. 18 b illustrates a side view of FIG. 17 a seen from right to left;

FIG. 19 a illustrates the top clamp of FIGS. 17 a-18 a, after thecontrol line has been cut and released, and shows the initial stage ofthe control line removal operation;

FIG. 19 b illustrates a side view of FIG. 19 a seen from right to left;

FIG. 20 a illustrates in a sectional view another embodiment of a topclamp further to the invention herein;

FIG. 20 b illustrates a side view of FIG. 20 a seen from right to left;

FIG. 21 a illustrates the top clamp of FIG. 20 a, and a wirelinemanipulation tool in engagement with it to perform a cut and releaseoperation of the control line;

FIG. 21 b illustrates a side view of FIG. 21 a seen from right to left;

FIG. 22 a illustrates the top clamp of FIGS. 20 a-21 a, after thecontrol line has been cut and released, and the system being ready forthe control line removal operation;

FIG. 22 b illustrates a side view of FIG. 22 a seen from right to left;

FIG. 23 a illustrates in a smaller scale a sectional view of a largerwell schematic, and the well status upon completing the manipulationstep illustrated in FIG. 22 a;

FIG. 23 b illustrates in a larger scale a detail of FIG. 23 a;

FIG. 24 a illustrates a first step of removing the control line based ona scenario as illustrated in FIG. 23 a;

FIG. 24 b illustrates in a larger scale a detail of FIG. 24 a;

FIG. 25 a illustrates a second step of removing the control line basedon a scenario as illustrated in FIG. 23 a;

FIG. 25 b illustrates in a larger scale a detail of FIG. 25 a;

FIG. 26 a illustrates a sectional view of an alternative arrangement forremoving the control line based on a scenario as illustrated in FIG. 23a;

FIG. 26 b illustrates in a larger scale a detail of FIG. 26 a; and

FIG. 27 illustrates a sectional view of an alternative embodiment forremoving the control line based on a scenario as illustrated in FIG. 23a.

In this document positional specifications such as “upper” and “lower”,“bottom” and “top” or “horizontal” and “vertical” refer to the positionof the apparatus in the figures, which may also be a natural, necessaryor practical functional position.

In FIG. 1 a borehole 101 is provided with a casing 102 used forpreventing the borehole from collapsing during drilling and subsequentproduction. In the lower section of the well, the casing 102 is cementedto the borehole 101, resulting in a section of what is referred to ascasing cement 103 herein; filling the annular area between the casing102 and the borehole 101. The casing cement 103 forms one of severalrequired fluid barriers between the underground, hydrocarbon carryingformation and the surface.

FIG. 1 illustrates a generic well completion wherein the lowercompletion comprises a production liner 104, which is cemented to theborehole using liner cement 105. The liner is open towards thehydrocarbon reservoir via perforations 106. The design and configurationof the production liner 104 may vary significantly from what isillustrated herein, however this will be appreciated by a person skilledin the art and not further described herein. The production liner 104 isanchored to and forms a seal towards the casing 102 by means of a linerhanger system 107.

The upper completion comprises a production tubing 108, which is stunginto the lower completion by means of a seal stinger assembly 109. Inthe bottom section of the tubing 108, this is terminated and forms aseal towards the casing 102 by means of a production packer 110. In thetop of the well, the tubing 108 is terminated in the lower section ofthe wellhead 111.

In the lower section of the tubing 108, a permanent downhole pressureand temperature gauge 112 is mounted. This is powered and communicatesto the surface by means of a control line 113.

In the top of the wellhead 111, an intervention bore 114 is blocked bytwo crown plugs 115. On the side of the wellhead 111, a flow line 116 isconnected to a production bore 117.

The completion design may vary significantly from what is shown in FIG.1, and there are common completion components that are not illustratedherein, such as a downhole safety valve. This is done consciously inorder to simplify the drawings, hence direct the focus on the design andmethods directly related to the invention described herein. Such factswill be appreciated by a person skilled in the art.

FIG. 2 illustrates relevant aspects in relation to prior art techniquesfor permanent plugging and abandonment of wells. In conjunction withsuch operations, heavy kill fluid is pumped into the well, whereupon adeep-set mechanical barrier 118 is installed. In conjunction with thekilling of the well, holes 119 are punched in the tubing 108 to allowfor displacement to kill fluid both on the inside and the outside of thetubing 108. As a next step, further to current practice, the tubing 108and control line 113 is cut, normally right above the production packer110, the cut being illustrated by the line A-A′. Then, the tubing 108and control line 113 is hauled out of the well using traditionalcasing/tubing handling equipment such as tongues and control line 108winches, or tailored jack based tubing retrieval systems on the surface.

The subsequent step in plugging and abandonment is the installation of acement retaining device 120, before a cement column referred to asabandonment cement 121 is dumped on top of the cement retainer 120. Itis a common requirement that the height of the abandonment cement 121column must equal or exceed a particular length L. In many cases, thelength L equals 50 meters. A final important requirement in this respectis that the abandonment cement 121 must fully overlap with the casingcement 103 in order to provide for the required pressure barrierfunction between the hydrocarbon carrying reservoir formation and thesurface.

In particular on fields developed by means of subsea well solutions,plug and abandonment operations can become very expensive, as thecurrent practice requires a drilling rig to perform the operation. Anobject of the present invention is to remove the need for a drilling rigto plug and abandon wells.

FIG. 3 illustrates a hypothetical situation, further to a scenariosought achieved by the invention described herein. In the scenarioillustrated in FIG. 3 the tubing is not pulled out of the well. Instead,the cement is pumped down the inside or bore of the tubing 108, throughthe holes 119 and up the annulus between the tubing 108 and the casing102 as illustrated in FIG. 3. The result is a column of abandonmentcement 121 that fills both on the inside and the annulus on the outsideof the tubing 108. Current regulations allow for such a method to beused, leaving the relevant section of tubing 108 encased by theabandonment cement 121. The only limitation is that the control line 113cannot be left inside along the permanent cement barrier. Currentregulations state that the control line 113 may form a future leak path;hence it needs to be removed prior to installing the cement 121. Thereis no current existing technique to remove control line 113 from theannular area between the tubing 108 and the casing 102. In order toavoid rig operations for performing the plug and abandonment work, thereis a need for an arrangement and a method for cutting and removing asection of control line 113 from the interval of length L as illustratedin FIG. 3.

FIG. 4 illustrates prior art technology for attaching the control line113 to the tubing 108. The main parts of the tubing 108 is made up oftubing joints 401 and collars 402. In normal cases, each tubing joint isapproximately 12 meters long. Common practice for installing a controlline 113 is to attach it to the tubing 108 using one cable clamp 403 percollar 402. There are several designs of cable clamps 403, the oneillustrated herein having bands 404 surrounding the tubing, the bands404 being located adjacent the shoulders of the collar 402. Thisprevents any sliding of the clamps 403 along the tubing 108 duringinstallation in the well. The clamp 403 is commonly a hinged design,manually installed when running the well completion. The clamps 403 aremounted on the tubing 108 as illustrated, whereupon the control line(s)is/are routed into grooves 405 of the clamp 403 prior to closing thisand tightening it up using torque bolts 406. As a part of this process,the control line 113 gets squeezed towards the tubing 108 via the mainshoulders 407 of the clamp 403, hence securing this from any slidingmovement along the length of the tubing 108. As per current practice,the removal of control line 113 from the annulus between the tubing 108and the casing 102 is difficult, as the orientation of the control line113 is unknown; the tubing 108 may be ex-centered inside the casing 102,the clamps 403 being made of very hard materials, difficult to cut etc.Finally, in relation to cutting the tubing 108 and the control line 113,there are regulatory requirements not to cause any damage to the casing102, making a cutting, allocation and retrieval process for the controlline 113 difficult.

According to the present invention, a well is completed in a differentmanner than what is performed today. More specifically, sections of thewell overlapping with the interval of length L in FIG. 3, are proposedcompleted by means of cable clamping arrangements having distinctivecharacteristic in order to facilitate for releasing, accessing andremoving the control line 113 over an interval that has an equal orexceeding overlap with the interval of length L in FIG. 3.

FIG. 5 illustrates a preferred embodiment of the invention. In theillustration clamping means comprising one top clamp 501, twointermediate clamps 502, 502′ and one bottom clamp 503 is illustrated.An important functionality related to these clamps 501, 502, 502′, 503is to secure the line 113 to the tubing 108 during installation of thewell completion and for the wells life. Essential functionalitycharacteristics in conjunction with the plugging and abandonment ofwells are:

-   -   The ability to perform a controlled splitting of the line 113        (typically done in the top clamp 501, the bottom clamp 503 or        both).    -   The ability to perform a controlled release of the line 113        (typically done in the top clamp 501 and bottom clamp 503 in        conjunction with a splitting/cutting operation, and for some        embodiments in the intermediate clamps 502, 502′    -   The ability to remove at least a majority of the line 113 from        an interval equal to or exceeding, and overlapping with the        interval L as described above—in a controlled manner.

There are several conceptual ways of achieving the above—some examplesare described in relation to the subsequent figures of this document.

In one embodiment of the invention, all of the control line 113 isremoved in one go. For this embodiment, the intermediate clamps 502,502′ are designed to allow for the controlled release of the controlline 113 from the tubing at these locations, without cutting the controlline 113.

In another embodiment, the control line 113 is removed sequentially. Inone associated embodiment the control line 113 is removed in sectionsthat for the most overlap with the length of the associated tubingjoints. In this case, the intermediate clamps 502, 502′ may not berelevant to use. In one related embodiment the top clamp 501 and bottomclamp 503 is merged into one uniform design, providing for both theability to split the relevant section of control line 113 as well asremoving this from the interval of relevance.

It should be emphasized that the clamps 501, 502, 502′, 503 describedherein are not needed for attachment of control line 113 along theentire well interval. They are only required for the interval where thecontrol line 113 needs to be cut/split, released and removed inconjunction with a plug and abandonment operation.

FIG. 6 illustrates the scenario where the control line 113 has beenremoved from the relevant interval by means of the techniques proposedherein. Do note that this normally takes place at a time where theinitial steps of a plug and abandonment operation is finished, hence theholes 119 are punched in the tubing 108 and the deep set mechanicalbarrier 118 is installed.

FIG. 7 illustrates the scenario where the relevant interval has beencemented; this is the new abandonment scenario further to the philosophyand techniques proposed herein. One final step of the abandonmentprocess not illustrated herein is related to the removal of the x-mastree 111, the flow line 116 and the upper sections of the casing 102.

As mentioned above, the exact design and number of the novel clamps thatare proposed herein may vary. In one embodiment of the invention, theoperation of relevant clamps such as the top clamp 501, intermediateclamp(s) 502, 502′ and bottom clamp 503 to perform the required plug andabandonment steps (such as splitting, releasing and accessing thecontrol line) is achieved by means of wireline manipulation techniques.In another embodiment, the operation is conducted by means of systemmanipulation via the control line 113. In still another embodiment, thecomponents are operated by means of mechanical systems, such asmechanical counters and activation mechanisms, operated by manipulatingtubing pressure, annulus pressure or both according to a pre-definedinterval of pressure impulses defined by amplitude, duration, frequencyand similar. In one embodiment, the operation is conducted by means of acombination of the above techniques.

FIG. 8 a and FIG. 8 b illustrates one embodiment of a bottom clamp 503associated with one embodiment of the invention. Do note that thefigures serve the purpose as non-limiting examples and illustrationsonly.

FIG. 8 a illustrates a sectional view of the bottom clamp 503 seen fromthe side, whereas FIG. 8 b illustrates the same section, uncut and asseen from the front looking from right to left in FIG. 8 a towards theside where the control line 113 is attached.

For this embodiment, the bottom clamp 503 replaces the collar 402 ofFIG. 4, meaning that the tubing joints 401 are screwed directly into thebottom clamp 503. Variations may apply, such as using crossovers to thetubing and similar. This will be appreciated by a person skilled in theart and not further described herein.

For this embodiment, the purpose of the bottom clamp 503 is merely toprovide for a controlled method of cutting the control line 113. Inorder to do this, the control line is located in a groove 801 in thebottom clamp 503, and fixed to the bottom clamp 503 using holding meansin the form of a block element 802 secured with bolts 803. Finally, thebottom clamp 503 includes allocation means in the form of an allocationand orientation profile 804 for a wireline tool to be used in the plugand abandonment operation. The profile 804 may be of similar design andshape as orientation/allocation wedges used in conjunction withinstallation of gas lift valves in side pocket mandrels. This will beappreciated by a person skilled in the art and is no further referred toherein.

FIG. 9 a and FIG. 9 b illustrate the process of cutting the line 113 forthe given embodiment of the bottom clamp 503. Here, a line manipulationapparatus in the form of a tailored wireline tool 901 is positionedcorrectly by means of an allocation bolt 902 orienting the tool 901 withrespect to the allocation profile 804. Note that the wireline tool 901is shown in a side view in FIG. 9 a and not in a sectional view as theclamp 503 and tubing 108. Then, a splitting means in the form of atransverse cutter element 903 is used to create a transverse cut 904 ofthe line 113 just above the block element 802. By means, the section ofline 113 that is located above the bottom clamp 503 has been split andreleased, and can now be pulled upwards.

FIG. 10 a and FIG. 10 b illustrate one embodiment of an intermediateclamp 502 associated with a similar embodiment of the invention as FIGS.8-9. The main difference from the bottom clamp 503 of FIGS. 8-9 is thatin FIG. 10, the control line 113 is attached to the clamp 502 by aholding means shown as a hinged block element 1001.

FIG. 11 a and FIG. 11 b illustrate the process of releasing the controlline 113 from the intermediate clamp 502 for this given embodiment ofthe invention. Similar to the process described in FIGS. 8-9, a wireline901 tool is applied for this purpose. The wireline tool 901 may be thesame as the one described in FIGS. 8-9 using different tool modules, ora different tool. However, in this document, number references forsimilar wireline tool modules are kept constant for simplicity purposes.

Again, the wireline tool 901 is positioned correctly by means of anallocation bolt 902 orienting the tool with respect to the allocationprofile 804. Then, a longitudinal cutter element 1101 is applied in apattern illustrated by arrow 1102 to create a longitudinal cut 1103 ofthe hinged block element 1001 as illustrated in FIG. 11 b. Thus, when asection of the control line 113 has been split and released above thelower block element 802 as illustrated in FIGS. 9 a and 9 b, the sectionof control line 113 that is located above the bottom clamp 503 and theintermediate clamp 502 can now be pulled upwards. By means, the hinge1001 does no longer impose any holding force on the control line 113. Inone embodiment, the hinge 1001 is designed to open somewhat when cut,for example by pre-tensioning it against a shoulder when tightening thebolts 803. The cutting element 1101 as well as other cutting elementsdescribed herein may be selected from the group comprising: mechanicalmeans such as blade/saw/grinder type cutters; plasma cutters; chemicalcutters; explosive cutters or a combination of one or more thereof. Thiswill be appreciated by a person skilled in the art and is no furtherreferred to herein.

In an alternative embodiment (not shown), the block element 1001 of theintermediate clamp 502 has a saw-tooth surface on the side that imposesforce on the control line 113. By means, this allows for one-way travelof the control line 113, and no cutting exercise is required to operatethis, simplifying the total operation of releasing and removing thecontrol line 113 from the interval of interest. This saw-tooth surfaceallows displacement of the control line 113 in one direction, but not inthe opposite direction. A similar saw-tooth surface can also be appliedon the part of the intermediate clamp 502 that the control line 113rests on, or on both the block element 1001 and the clamp 502.

The control line 113 associated with the top clamp 501 and/or bottomclamps 503 could also be designed having a self-disconnect system toremove the need to cut or manipulate the line 113 loose from the clampbeing in the opposite end of where it is intended to pull/push thecontrol line 113 out of the annular segment in question.

As would be appreciated by a person skilled in the art, combinations ofthe above features could also be included in relevant embodiments, suchas the inclusion of a saw-tooth or similar one-way feature of blockelements 802 shown in FIGS. 8 and 9 associated with top- or bottomclamps 501, 503.

FIG. 12 a and FIG. 12 b illustrate one embodiment of a top clamp 501associated with a similar embodiment of the invention as in FIGS. 8-11.As for the bottom clamp 503 of FIGS. 8-9, the control line 113 isattached to the clamp 502 by means of a block element 802.

The main difference is that the top clamp 501 is provided with a pullingprofile 1201 on its internal wall, adjacent to the block element 802.

FIG. 13 a and FIG. 13 b illustrate the process of releasing the controlline 113 from the top clamp 501 for the given embodiment of theinvention as described in FIGS. 8-11, and moreover the process ofremoving the control line 113 from the relevant section of the well.Here, the wireline tool 901 is positioned in a similar way to what wasdescribed for the previous figures. A latching/gripping element 1301 ofthe wireline tool 901 is operated to engage with the pulling profile1201. A multi directional cutter 1302 is applied to make a rectangularshaped cut 1303, surrounding the entire block element 802. A groove 1304is included in the arrangement to provide for space between the cuttingelement and the control line 113. The intention with the space is toavoid accidentally cutting the control line 113 below the block element802. The reason for avoiding cutting the control line below the blockelement 802 will be apparent by studying FIGS. 14 a and 14 b. Suchprotection against accidental cutting could be sought in various ways.This would be appreciated by someone skilled in the art and is nofurther referred to herein. The rectangular cut 1303 may be difficult tomake in one go, whilst the latching element 1301 is engaged to thepulling profile 1201. In one embodiment, one or more of the cuttingoperations required to create the cut 1301 is/are performed prior toengaging the latching element 1301 to the pulling profile 1201, whereasthe remaining cutting operations are performed after engagement.

FIG. 14 a and FIG. 14 b illustrate the process of removing the controlline from the relevant section in the well for this given embodiment,following the operative steps described in FIGS. 8-13. Here, thelatching element 1301 is retracted into the body of the wireline tool901, bringing the pipe segment defined within the rectangular shaped cut1303 holding the block element 802 with it. As the block element 802still exerts a strong holding force on the control line 113, this cannow be pulled out by means of the wireline tool 901. In one embodiment,the control line is pulled all the way to the surface and displaced of.This embodiment may entail a challenge with respect to wirelinelubricator space required to bring out a >50 meter long object. Inanother embodiment, the wireline is used to lower the control line 113segment to a location below the interval L to be cemented (see FIG. 7)and drop it, hence dispose of it in that section of the well. Thus, inFIG. 14 a the wireline tool 9001 is both a manipulation apparatus and aretrieval apparatus arranged for bringing or displacing the portion ofthe line 113 from the outside to the inside of the tubing 108.

FIG. 15 a and FIG. 15 b illustrate a slightly different arrangement andmethod to achieve the same result as described in relation to FIGS.12-14. Here, the top clamp 501 is provided with a wedge ring 1501 whichhas a wedge protrusion 1502 as an integral part of it. When installed,the wedge ring 1501 is compressing a spring 1503, which again forces thewedge protrusion 1502 down abutting the block element 802. By means,when making a similar square cut 1303 as illustrated in FIG. 14 b, thewedge protrusion biased by the spring 1503 will urge the piece that iscut loose inwards towards the center or bore of the tubing 108. This isillustrated in FIGS. 16 a and b. A potential benefit with thisembodiment is that the tubing piece that is cut loose now can becollected by means of a collector module 1504 of the wireline tool. Sucha collector module 1504 may provide a more simple design and hence morereliable than the latching element 1301 of the previous embodiment.Moreover, the collector module 1504 may not cause the same spatialconflicts with the cutter 1302 when creating the cut 1303 as could bethe situation with the latching element 1301.

One main benefit with the embodiments described in FIGS. 8-16 is thatthe clamp modules do not introduce any new leakage points to thecompletion than what already exist between tubing joints and collars asper current practice. However, the embodiments shown in FIGS. 8-16requires relatively sophisticated wireline tooling to operate. In thefollowing section, alternative embodiments, in particular embodimentsthat do not require pipe cutting modules are illustrated.

FIG. 17 a and FIG. 17 b show an alternative embodiment of the top clamp501. A pulling profile 1201 is integrated in a modular pipe wall segment1701, which is initially integrated in the top clamp 501. A seal 1702provides for the barrier integrity between the inside and outside of thetubing 108. The pipe wall segment 1701 is fixed to the top clamp 501 bya locking means, which in the embodiment shown is a lock pin 1703initially located in a locking position inside a lock groove 1704. Forthe illustrated embodiment, the lock pin 1703 forms an integral part oflock ring 1705, which is initially held in a lower (locking) position bylock spring 1706. Finally, for this embodiment the top clamp 501includes a splitting means in the form of a cutting module 1707, such asa cutting blade.

FIG. 18 a and FIG. 18 b illustrate the initial operating step of the topclamp 501 embodiment from FIG. 17 at a stage where plug and abandonmentactivities have been initiated. As described for the embodiment above, atailored wireline tool 901 is positioned correctly by means of anallocation bolt 902 orienting the tool with respect to the allocationprofile 804. Then, a latching/gripping element 1301 of the wireline tool901 is operated to engage with the pulling profile 1201. The next stepis to unlock or release the pipe wall segment 1701 from the top clamp501. This is done by operating a lock manipulation module 1801 of thewireline tool 901. For this embodiment, the lock manipulation module1801 engages with the lock ring 1705 and pushes this upwards, asindicated by arrow 1802. This causes the lock pin 1703 to disengage fromthe lock groove 1704. Upon removing the lock function, the pipe wallsegment 1701 can be disengaged from the top clamp 501 by means ofoperating the latching/gripping element 1301 of the wireline tool 901.When pulling the wall segment 1701 inwards, the cutting module 1707 cutsthe control line 113. This is further illustrated in FIG. 19 a and FIG.19 b. Subsequently, the control line 113 can be pulled out of the well,alternatively removed from the well interval to be cemented and disposedof elsewhere in the well.

Again, it is emphasized that details shown in this document illustratepossible system functions only. For example, the number and design oflocks related to the embodiment shown in FIGS. 17-19 may vary, and mayin alternative embodiments vary significantly from what is illustratedherein, however the functionality remains similar.

FIG. 20 a and FIG. 20 b show yet another embodiment of the top clamp501. A portion of the control line 113 runs through a sealed cavity 2001defined by an outer cover lid 2002, the body of the top clamp 501, andan inner mandrel 2003. The inner mandrel 2003 seals against the cavity2001 by means of mandrel seals 2004, 2004′. The cover lid 2002 sealsagainst the cavity by means a cover seal 2005 and line seals 2006,2006′. The line seals 2006, 2006′ surround the control line 113, to forma seal around this.

Experts in the art will appreciate that the task of obtaining 100% tightseals may be challenging from design, operational and material relatedperspectives. In one embodiment of the invention, the seals 2006, 2006′(as well as the other seals described herein) may therefore not bepressure proof seals, but rather functioning as efficient flowrestrictors, enabling the operation of pumping the control line 113 outof the annulus between the tubing 108 and casing 102 using techniques tocreate a pressure differential across seals 2006, 2006′. This isexplainer further in the following paragraphs.

FIG. 20 a discloses a mandrel 2003 provided with a wireline engagementprofile 2007. The top clamp 501 is provided with a mandrel recess 2008to allow for a defined longitudinal displacement of the mandrel 2003.

Inside the cavity 2001, the control line 113 is attached to the mandrel2003 by means of an attachment clamp 2009. Also, inside the cavity 2001,the control line 113 is thread through a cutting module 2010 that formsan integral part of the cover lid 2002.

In a preferred embodiment, the segment of control line 113 inside thecavity 2001 has a stop system associated with it, preventing it frombeing pumped into the annulus on the outside of the tubing 108. Such astop system could involve one-way, saw-tooth profiled surfaces where thecontrol line 113 is resting against the lid 2002 or the solid body ofthe top clamp 501. Alternatively, such a stop system be achieved byproviding geometrical anomalies on the control line 113, such as forexample arranging stop rings on the line, that have a size that does notallow for the control line 113 to be pumped backwards through the lineseals 2006, 2006′ and into the annulus.

FIG. 21 a and FIG. 20 b illustrate the engagement of a mandrelmanipulation wireline tool 2101 to the engagement profile 2007 of themandrel 2003. More specifically, engagement dogs 2102 of the wirelinetool 2101 are in engagement with the profile 2007.

FIG. 22 a and FIG. 22 b illustrate the wireline tool 2101 pulling themandrel 2003 upwards. This results in the cavity 2001 being openedtowards the bore of the tubing 108. In the same process, the clamp 2009with the control line 113 attached to it moves upwards with respect tothe cutting module 2010, resulting in the control line 113 being cut bythe cutting module 2010. For the illustrated embodiment, this entails aloose end 2201 of the control line 113 being positioned adjacent to anopening 2202 between the cavity 2001 and the bore of the tubing 108.

In one embodiment, similar features as those shown in FIGS. 20-22 areassociated with the bottom clamp 503 rather than the top clamp 501. Insuch embodiments, the top clamp 501 may only have features related tosplitting and releasing the control line 113 inside it, and no featurefor creating the said opening 2202 between the cavity 2001 and the boreof the tubing 108. One reason for swapping the said functionalitiesbetween the top clamp 501 and the bottom clamp 503 is that it may bedesired to pump the control line 113 downwards into the well during thesubsequent operational step(s).

One such scenario is described in FIG. 23 a and FIG. 23 b illustratingthe resulting status of the well and control line system after theoperation of a bottom clamp 503 according to a method as illustrated inFIG. 20-22. The control line system is defined by the control line 113having one loose end 2201 exposed to the bore of the tubing 108, theseal 2006 forming a seal between the bore of the tubing 108 and theannulus between the tubing 108 and the casing 102. For this embodimentand given status of the well operation, the control line 113 has beensplit and released in the top clamp 501, and also released from theintermediate clamps 502, 502′. An “x” is used to illustrate the factthat these modules have been operated according to said functions,despite the control line 113 still being illustrated to run throughthem.

FIG. 24 a and FIG. 24 b illustrate one technique for retrieving thecontrol line 113 further to a scenario defined in FIG. 23. In FIG. 24 aand FIG. 24 b a control line collecting wireline tool 2401 is intervenedinto the well. The tool 2401 comprises a lower collector chamber 2402,with at least one collector port 2403 being positioned adjacent to theloose end 2201 of the control line 113. The lower collector chamber 2402module also includes a lower packer element 2404 and an upper packerelement 2405 that, when in a “control line 113 retrieval position”,straddles the opening 2202 of the bottom clamp 503 illustrated in FIG.22 a, including the seal 2006. The wireline tool 2401 also includes asuction chamber 2406 containing a gas, typically air, at a low pressure,equal or close to atmospheric pressure. The collector chamber 2402 andthe suction chamber 2406 are initially separated by a piston 2407.

When the wireline tool 2401 is correctly positioned, as illustrated inFIG. 25 a and FIG. 25 b, and the packer elements 2404, 2405 are engagedto the tubing 108, the piston 2407 is released. Methods for releasingsuch pistons will be appreciated by a person skilled in the art and istherefore not described in any further details herein. Now, the piston2407 travels up into the suction chamber 2406, due to the pressuredifference between the suction chamber 2406 and the surroundings. As thepacker elements 2404, 2405 forms an enclosure as illustrated in thefigure, the control line 113 is forced towards the inside of the tubing108 and the collector chamber 2402, driven by the high pressure beingpresent in the annulus between the tubing 108 and the casing 102. Theresult is a separated control line segment 2501 being collected into acollector chamber 2406 in a controlled fashion.

This embodiment and method may have a challenge in relation to detectingwhether or not all of the control line 113 has been removed from theinterval L (se FIG. 3). In one embodiment, monitoring of pressure in theannulus between the tubing 108 and the casing 102 is used to detectpressure change indications verifying that all the control line 113 hasbeen removed from the relevant interval.

FIG. 26 a and FIG. 26 b illustrate a slightly different embodiment ofthe wireline collector tool 2401. Here, the piston 2407 has beenreplaced by a channel 2601, located above the upper packer element 2405.Instead of using an atmospheric suction chamber 2406 as illustrated inFIG. 24 a and FIG. 24 b, the control line is removed from the interval L(see FIG. 3) by pumping fluids down the annulus between the tubing 108and the casing 102 using a surface pump (not shown), whilst openingvalves on the top of the well, allowing for a return of the same fluidvia the bore of the tubing 108. By means, the control line 113 will bepumped out of the interval L and into the collector chamber 2402 of thewireline tool 2401. In one embodiment of the invention, the channel 2601includes a filter (not shown) to prevent the control line 113 beingpumped out of the wireline tool 2401.

For the method of pumping out the control line 113 by pumping down theannulus; in one embodiment of the invention, the pressure patterns onthe surface is monitored, on the pump side or on the return side orboth, to observe for a pressure change associated with the control line113 no longer plugging the center channel of the seal 2006. Forscenarios where the well is completed with multiple control lines 113the entry to the channel of the seal 2006 may be provided with a ball orsimilar that is adapted to drop into and plug the channel when the line113 is pumped out of it. This would entail a pressure change when allthe lines are pumped out of the interval, and the system channels isplugged by components that are prevented from moving. Alternative socalled tell-tale systems indicating when the control line has been fullyremoved from the interval could be envisaged. Such tell-tale systemswould be appreciated by a person skilled in the art.

Do note that the deep set barrier 118 forms a sealed enclosure towardsthe bottom section of the well, providing for a pumping/circulationpattern as described above, and preventing unwanted so calledbullheading of fluids into the reservoir.

FIG. 27 illustrates an embodiment where no wireline tool is used tocollect the control line 113 that has been pumped out. Instead, for thisembodiment, the control line 113 is allowed to free-fall to a section ofthe well where it is left permanently. In one embodiment of theinvention, the control line 113 falls to a section of the well that doesnot overlap with the interval L to be cemented. In one embodiment of theinvention, a wireline tool 901 is used to force the control line 113down and bundle it to a more compact form, ensuring that it does notoverlap with the interval L to be cemented.

In another embodiment of the invention, similar techniques are used todisplace the control line 113 to other locations inside the tubing 108,as well as to other locations inside the annulus between the tubing 113and the casing 102. The important aspect is that the control line 113originally located across the interval “L” of FIG. 3 has been removedfrom the interval, and to a location where it does not conflict with thesubsequent cementing operations as well as other subsequent operationsof the well abandonment operation.

In some scenarios, a well may be completed with multiple control lines113. Control lines 113 may also be one or a combination of electric andhydraulic control lines 113. For the removal of hydraulic control lines113, pumping and/or suction techniques described herein, such as thetechniques described in FIGS. 22-26, may not be directly applicable, asa hydraulic control line 113 is hollow, and will allow flow through thebore therein. For such cases, it may be required to provide for a methodof sealing the bore of the line 113 prior to utilizing pumping orsuction methods to remove it from the interval L. In one embodiment, thearrangement and method for cutting the control line 113 segment to beremoved in the opposite end of the loose end 2201 adjacent to theopening 2202 as illustrated in FIG. 22, would include a method forsealing off the control line 113 in such an opposite end. In oneembodiment, such method for sealing would entail mechanical deformationof the control line 113. In another embodiment, check valvefunctionality is activated at this instance. For the latter case, themethod for splitting“cutting” the control line 113 may not be mechanicalcutting, but rather a controlled disconnection of the control line 113at a point designed in order to facilitate for this (i.e. a linecoupling designed for such purposes), meaning that the control line 113as well as the surrounding well mechanics and manipulation devices havebeen designed for performing a controlled disconnection and sealing ofthe control line 113 at such point. Techniques for this would beappreciated by a person skilled in the art.

As a final remark, it should be emphasized that the method according tothe invention provides for retrieving or producing out the control line113 in both the top as well as the bottom end of the indicatedtop/intermediate/bottom clamp 501,502,503 assembly, and that thefunctionality of the clamp systems 501, 502, 503 as described in theexamples provided herein could be interchanged, so that for alternativeembodiments the functionality shown for the top clamp 501 herein wouldapply for a bottom clamp 502 and vice versa. Moreover, the inventionprovides for sequential removal of the relevant length of control line,such as sectional movement of control line 113 between two and twoclamps 501, 502, 503, respectively—potentially removing the need forintermediate clamps 502, 502′. In the latter case, the term “release ofcontrol line 113” referred to herein would not be associated with therelease of control line 113 from an intermediate clamp 502, but therelease from a top clamp 501 or bottom clamp 503. In one embodiment therelease activity takes place simultaneously to the cutting/splittingactivity. To achieve splitting, release and removal of control line(s)113 from the annulus between the tubing 108 and the casing 102, featuresas described or illustrated herein, as well as any combination ofdescribed features could form part of relevant embodiments.

In one embodiment of the invention, the operation of relevant clampssuch as the top clamp 501, intermediate clamp(s) 502/502′ and bottomclamp 503 to perform the required plug and abandonment steps, such ascutting/splitting, releasing and removing the control line 113, isachieved by means of wireline manipulation techniques. In anotherembodiment, the operation is conducted by means of system manipulationvia one or multiple control line(s) 113 in a similar way to howso-called smart well components of wells are manipulated. As an example,the mandrel 2003 of FIG. 20 could be manipulated to provide for thecutting/splitting, release and removal of control line 113 by operationscontrolled via the control line 113 using known actuating techniquessuch as hydraulic, electro hydraulic or electric actuation, or othertechniques appreciated by a person skilled in the art. In still anotherembodiment, relevant components are operated by means of mechanicalsystems, such as mechanical counters and activation mechanisms, operatedby manipulating tubing pressure, annulus pressure or both according to apre-defined interval of pressure impulses defined by amplitude, durationand similar. Norwegian patent application NO 20110246 filed by thepresent applicant describes one such arrangement and technique. In oneembodiment the above operations are conducted using wireless techniques,and that autonomous, remotely operated downhole arrangements perform oneor more of the required cut/split, release and remove operations. In oneembodiment, the operation is conducted by means of a combination of theabove techniques. Provided an otherwise equal parameter comparison; thelatter described methods (the methods not requiring wirelinemanipulation) would be preferred over methods that require wirelinemanipulation, as the cost of conducting a wireline operation can becomesomewhat high in comparison.

In one embodiment, the clamping means 501, 502, 503 are not in the formof collars that replaces the collar 402 of FIG. 4. In some embodimentsthey may be designed in a similar fashion as prior art cable clamps 403illustrated in FIG. 4. For such embodiments, the clamping means 501,502, 503 and holding means 802, 1001, 2009 may be merged into one commonfunctionality. Moreover, for such cases, the collars 402 may be providedwith external orientation profiles to enable the mounting of theclamping means 501, 502, 503 with an orientation that provides for theuse of techniques described herein, and internal orientation profiles804, 2007; 902, 2102 for the orientation of manipulation devices asdescribed herein.

1. A well completion arrangement for removing at least a portion of aline running in an annulus between a tubing and a casing in a well, thearrangement comprising: at least two clamping means spaced apart in thelongitudinal direction of the tubing and fixed thereto, the clampingmeans being configured for fixing the line with respect to tubing;splitting means for releasing the line from the interval defined by atleast an upper clamping means and a lower clamping means of the at leasttwo clamping means; a line manipulator apparatus, for activating saidrelease of the line; a line retrieval apparatus for displacing into thetubing the portion of the line from said interval, thereby removing theline from the annulus.
 2. The well completion apparatus according toclaim 1, wherein the clamping means constitutes a portion of the tubingconnecting two tubing joints (401), or associated crossover pipingtowards the tubing.
 3. The well completion arrangement according toclaim 1, wherein the arrangement is provided with an allocation meansfor controlling the position of at least the manipulator apparatus (901,2101) with respect to the holding means.
 4. The well completionarrangement according to claim 1, wherein the line manipulator apparatuscomprises the line retrieval apparatus.
 5. The well completionarrangement according to claim 1, wherein the splitting means isprovided in at least one of the clamping means.
 6. The well completionarrangement according to claim 1, wherein the splitting means isprovided in the manipulator apparatus.
 7. The well completionarrangement according to claim 1, wherein the splitting means is adaptedto cut through a portion of the clamping means.
 8. The well completionarrangement according to claim 1, wherein the line manipulator isfurther provided with gripping means adapted for engaging a profile ofthe clamping means, the profile being arranged adjacent of the holdingmeans.
 9. The well completion arrangement according to claim 1, whereinthe retrieval apparatus is at least one of a flow and pressure inducingapparatus arranged for displacing the line from the outside to theinside of the tubing.
 10. The well completion arrangement according toclaim 9, wherein at least one of the flow and pressure inducingapparatus is a pump located on the surface of the well.
 11. A method ofpreparing a well for abandonment, the method comprising: incorporatingat least two spaced apart clamping means in a tubing during completionof the well, the clamping means being provided with a holding means forfixing a line with respect to the clamping means, the line running in anannulus between the tubing and a casing; providing splitting means forreleasing the line at least at an upper clamping means and at a lowerclamping means of the at least two clamping means, providing anapparatus for inducing said release of the line; and providing anapparatus for displacing into the tubing the portion of the line fromthe interval defined by at least the upper clamping means and at thelower clamping means of the at least two clamping means.